US drugmaker Johnson & Johnson (J&J) is close to a vaccine licensing deal with South African group Aspen Pharmacare, a senior J&J executive told a conference in Nigeria on Wednesday.

"We are at the advanced stages of a potential licensing agreement with Aspen and we are really hopeful it will be finalised," said Stacy Meyer, J&J's Vice President Global Public Health, Operations and Partnerships. She gave no further details.

In November, Aspen signed non-binding terms with subsidiaries of J&J, saying this was a step towards a licensing deal for Aspen to package and sell J&J's's Covid-19 vaccine in Africa.

The non-binding agreements were hailed by the World Health Organization as a "transformative moment" in the drive towards greater vaccine equity.

Africa is the least vaccinated part of the world. Multiple organisations and companies are involved in initiatives to build up vaccine manufacturing capacity on the continent, to avoid a repeat of what happened at the start of the Covid-19 vaccination drive, when rich countries hoarded supplies.